1. Field of the Invention
The present invention relates generally to an improved data processing system, and in particular to a computer implemented method, data processing system, and computer program product for providing a management software approach to automatic and dynamic migration of applications running within virtualized process collections while retaining state during the migration operation.
2. Description of the Related Art
A virtualized process collection (VPC) is an assembly of processes which comprise the runtime instance of a specific application, such as Websphere or DB2, deployed within a logical partition of an operating system. This collection can also be described as a container which can be relocated or migrated between logical partitions (LPARs). In some systems, these virtualized process collections may be migrated from one server or physical device to another (i.e., mobility operation) to allow for load balancing the processes across the system.
Virtualized process collections can be moved manually under administrative control or using a system capable of moving the collections automatically. The latter is the most flexible approach. The ability to move virtualized process collections results in a data center that behaves rapidly to changes in its resource usage characteristics without the intervention of operators or administrators in most cases. This dynamic mobile application environment is referred to as “Utility Computing” (UC). Utility Computing is concerned with the management of virtualized process collections, with the focus on mobility to achieve a highly dynamic data center.
Examples of virtual server migration technologies include AIX® Workload Partition (WPAR), Linux® Workload Partition (WPAR), EMC's V-Motion™, and the Xen Virtual Management (VM) Console. A Workload Partition (WPAR) instance is a portion or representation of a system within an operating system. A virtualized process collection can be defined as the collection of processes running within a virtual server partition. A Workload Partition defines the container for a virtualized process collection. Other containers for a virtualized process collection may include a VMWare partition or a Xen VM instance.
When migrating a process from a source system to a target system, such as from one server or physical device to another or from one system partition to another partition within the same server, some current virtual server solutions such as EMC's V-Motion™ and the Xen VM Console do not allow for automatic migration, providing only manually triggered mobility and leaving target selection completely up to the user. Other virtual server mobility technologies, such as the AIX® and Linux® WPAR products, provide the ability for automatically migrating a WPAR instance or virtualized process collection to another partition. However, automation of virtual server technologies requires some sort of mechanism to rank available target server partitions for migration to ensure that the partition with the most appropriate performance characteristics is selected as the migration target based on the current performance state of the WPAR or virtual machine instance.